Optical Module

ABSTRACT

The present disclosure discloses an optical module including: a circuit board; a housing assembly divided by a separation board into a first portion and a second portion that are stacked one above the other, wherein a light-emitting cavity is formed in the second portion, and a partition wall is provided in the first portion to separate the first portion into a light-receiving cavity and a slot, and is provided with a plurality of light-passing holes via which the light-receiving cavity is in communication with the slot; an optical fiber adapter disposed in the housing assembly and in communication with the light-receiving cavity; a light-emitting assembly arranged in the light emitting cavity and electrically connected to the circuit board, wherein heat generated by the light-emitting assembly is conducted to a surface of the housing assembly via the partition wall; and a light-receiving assembly.

CROSS-REFERENCE TO RELATED APPLICATION

This disclosure is a continuation application of PCT/CN2021/100998,filed Jun. 18, 2021, and claims the priority to the Chinese patentapplication No. 202011475117.7, filed with the China NationalIntellectual Property Administration on Dec. 14, 2020 and entitled“Optical Module”, the Chinese patent application No. 202011475053.0,filed with the China National Intellectual Property Administration onDec. 14, 2020 and entitled “Optical Module”, and the Chinese patentapplication No. 202011466271.8, filed with the China NationalIntellectual Property Administration on Dec. 14, 2020 and entitled“Optical Module”, all of which are incorporated herein by reference intheir entireties.

FIELD OF THE PRESENT DISCLOSURE

The present disclosure relates to the field of optical communicationtechnologies, and in particular, to an optical module.

BACKGROUND OF THE PRESENT DISCLOSURE

With the development of new business and applications such as cloudcomputing, mobile internet, and video, etc., developments and progressesfor optical communication technologies have become more and moreimportant. In optical communication technologies, an optical module is atool for achieving mutual conversion between optical signals andelectric signals, and is one of the key devices in an opticalcommunication equipment. With the developments in the opticalcommunication technologies, a transmission rate of the optical modulecontinues to increase.

Usually, the number of transmission channels in the optical module maybe increased for improving a transmission rate for an optical module;for example, an optical module comprising a set of light-emittingsub-modules (which emits lights with one wavelength) and a set oflight-receiving sub-modules (which receives lights with one wavelength)is improved to comprise two sets of light-emitting sub-modules (each setemits lights with one wavelength) and two sets of light-receivingsub-modules (each group receives lights with one wavelength). In thisway, in the optical module, the volume occupied by the light-emittingsub-modules and the light-receiving sub-modules in the optical modulewill continue to increase, which is in turn not beneficial for furtherdevelopment of the optical module.

SUMMARY OF THE PRESENT DISCLOSURE

In a first aspect, the present disclosure discloses an optical module,including: a circuit board; a housing assembly into which the circuitboard is inserted, which is divided by a separation board into a firstportion and a second portion that are stacked one above the other,wherein a light-emitting cavity is formed in the second portion, and apartition wall is provided in the first portion to separate the firstportion into a light-receiving cavity and a slot that is arrangedapproximate to the circuit board, wherein the partition wall is providedwith a plurality of light-passing holes via which the light-receivingcavity is in communication with the slot; an optical fiber adapter,which is arranged in the housing assembly at a side away from thecircuit board, and is in communication with the light-receiving cavity;a light-emitting assembly, which is arranged in the light emittingcavity and is electrically connected to the circuit board, wherein heatgenerated by the light-emitting assembly is conducted to a surface ofthe housing assembly via the partition wall; and a light-receivingassembly, which includes a wavelength-division multiplexing component, alens array and a light-receiving chip, wherein the wavelength-divisionmultiplexing component is arranged in the light-receiving cavity fordemultiplexing a multiplexed beam transmitted by the optical fiberadapter into multiple beams of different wavelengths and transmittingthe demultiplexed multiple beams to the lens array through respectivelight-passing holes; wherein the lens array is arranged in the slot forconverging the multiple beams transmitted through the light-passingholes onto the light-receiving chip; wherein the light-receiving chip isarranged on an end surface of the circuit board that is inserted withinthe housing assembly for receiving the converged beams and convertingthem into a current signal.

In a second aspect, the present disclosure discloses an optical moduleincluding: a circuit board; a housing assembly, which is divided by aseparation board into a light-receiving portion and a light-emittingcavity that are stacked one above the other, wherein the light-receivingportion is provided with a plurality of light-passing holes, wherein thecircuit board is inserted into the housing assembly; an optical fiberadapter, which is arranged in the housing assembly at a side away fromthe circuit board, and is in communication with the light-emittingcavity; a light-receiving assembly, which is arranged in thelight-receiving portion and is electrically connected with the circuitboard; and a light-emitting assembly, which is arranged in thelight-emitting cavity and is electrically connected to the circuitboard; wherein the light-emitting assembly includes a wavelengthdivision multiplexing component, a lens array and a laser assembly, andthe laser assembly, the lens array and the wavelength divisionmultiplexing component are disposed in sequence along a light-emittingpath, wherein the laser assembly is arranged underneath thelight-passing holes for emitting multiple beams of differentwavelengths; wherein the lens array is configured to convert themultiple beams into multiple collimated beams; the wavelength divisionmultiplexing component is configured to multiplex multiple collimatedbeams into a multiplexed beam and to couple the multiplexed beam to theoptical fiber adapter.

In a third aspect, the present disclosure discloses an optical moduleincluding: a circuit board, an upper surface of which is provided with alight-receiving chip, and a lower surface of which is provided with apad; a housing assembly, an upper surface of which is downwardlyrecessed to form a light-receiving cavity and a slot, with a partitionwall being provided between the light-receiving cavity and the slot,wherein the partition wall is provided with light-passing holes tocommunicate the light-receiving cavity with the slot; wherein a lowersurface of the housing assembly is upwardly recessed to form alight-emitting cavity; a first optical fiber adapter, which is arrangedat one end of the light-receiving cavity; a third optical fiber adapter,which is arranged at one end of the light-emitting cavity, with a notchbeing provided at the other end of the light-emitting cavity; alight-emitting assembly, which is arranged in the light-emitting cavityand is configured to transmit lights to the third optical fiber adapter;wherein one end of the circuit board protrudes into the light-emittingcavity via the notch; the pad is arranged in the light-emitting cavityand is connected with the light-emitting assembly by wires; an opticalcomponent, which is arranged in the light-receiving cavity and isconfigured to receive lights from the first optical fiber adapter; areflective mirror, which is disposed at the slot and reflects lightsfrom the optical component; and a light-receiving chip, which isarranged between the reflective mirror and the circuit board and islocated outside the housing assembly, and is configured to receivelights from the reflective mirror.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a connection relationship of opticalcommunication terminals;

FIG. 2 is a schematic structural diagram of an optical network terminal;

FIG. 3 is a schematic structural diagram of an optical module accordingto embodiments of the present disclosure;

FIG. 4 is a schematic exploded diagram of an optical module according toan embodiment of the present disclosure;

FIG. 5 is a schematic assembly diagram of a circuit board and an opticalsub-module in an optical module according to an embodiment of thepresent disclosure;

FIG. 6 is a schematic exploded diagram of a circuit board and an opticalsub-module in an optical module according to an embodiment of thepresent disclosure;

FIG. 7 is a schematic partial structure diagram of an optical sub-modulein an optical module according to an embodiment of the presentdisclosure;

FIG. 8 is a working principle diagram of a demultiplexer (DeMUX)according to an embodiment of the present disclosure;

FIG. 9 is a schematic structural diagram of a housing assembly in anoptical module according to an embodiment of the present disclosure;

FIG. 10 is a schematic structural diagram from another angle of view fora housing assembly in an optical module according to an embodiment ofthe present disclosure;

FIG. 11 is a partial cross-sectional view of a housing assembly in anoptical module according to an embodiment of the present disclosure;

FIG. 12 is a schematic structural diagram of a light-receiving assemblyin an optical module according to an embodiment of the presentdisclosure;

FIG. 13 is a schematic diagram of an optical path of a light-receivingassembly in an optical module according to an embodiment of the presentdisclosure;

FIG. 14 is a cross-sectional view of a light-receiving assembly arrangedin a housing assembly of an optical module according to an embodiment ofthe present disclosure;

FIG. 15 is a cross-sectional view of a light-receiving assemblyassembled with a circuit board in an optical module according to anembodiment of the present disclosure;

FIG. 16 is a schematic diagram from another angle of view for an opticalsub-module assembled with a circuit board in an optical module accordingto an embodiment of the present disclosure;

FIG. 17 is a schematic diagram from yet another angle of view for anoptical sub-module assembled with a circuit board in an optical moduleaccording to an embodiment of the present disclosure;

FIG. 18 is an exploded diagram from another angle of view for an opticalsub-module assembled with a circuit board in an optical module accordingto an embodiment of the present disclosure;

FIG. 19 is a schematic partial structural diagram from another angle ofview for an optical sub-module in an optical module according to anembodiment of the present disclosure;

FIG. 20 is a schematic structural diagram of a light-emitting assemblyin an optical module according to an embodiment of the presentdisclosure;

FIG. 21 is a schematic diagram showing an optical path of alight-emitting assembly in an optical module according to an embodimentof the present disclosure;

FIG. 22 is a schematic structural diagram from another angle of view fora housing assembly in an optical module according to an embodiment ofthe present disclosure;

FIG. 23 is a cross-sectional view of a light-emitting assembly assembledin a housing assembly of an optical module according to an embodiment ofthe present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereinafter, technical solutions in some embodiments of the presentdisclosure will be described clearly and completely with reference tothe accompanying drawings. Obviously, the described embodiments merelyshow some but not all embodiments of the present disclosure. All otherembodiments obtained by a person of ordinary skill in the art based onthe embodiments of the present disclosure shall fall within theprotection scope of the present disclosure.

In the description of the specification, the terms “one embodiment”,“some embodiments”, “exemplary embodiment(s)”, “an example”, “a specificexample” or “some examples” etc. are intended to indicate that specificfeatures, structures, materials or properties related to theembodiment(s) or example(s) are comprised in at least one embodiment orexample of the present disclosure. Schematic representations of theabove terms do not necessarily refer to the same embodiment(s) orexample(s). In addition, the specific features, structures, materials orcharacteristics described may be comprised in any one or moreembodiments or examples in any suitable manner.

Hereinafter, the terms “first” and “second” are used for descriptivepurposes only, and are not to be construed as indicating or implying therelative importance or implicitly indicating the number of indicatedtechnical features. Thus, features defined with “first” and “second” mayexplicitly or implicitly comprise one or more of the features. In thedescription of the embodiments of the present disclosure, “plurality”means two or more unless otherwise specified.

In describing some embodiments, the expression “connected” and itsderivatives may be used. For example, the term “connected” may be usedin the description of some embodiments to indicate that two or moreparts are in direct physical or electrical contact with each other.However, the term “connected” may also mean that two or more parts arenot in direct contact with each other, but still cooperate or interactwith each other. The embodiments disclosed herein are not necessarilylimited by the contents herein.

The use of the term “configured to” herein is meant to be open andinclusive, and is not meant to exclude a situation that that the deviceis configured to perform additional tasks or steps.

Additionally, the use of the term “based on” is meant to be open andinclusive, as a process, step, calculation or other actions “based on”one or more of the stated conditions or values may in practice be basedon additional conditions or values.

FIG. 1 is a schematic diagram of a connection relationship of opticalcommunication terminals. As shown in FIG. 1, the connection of theoptical communication terminals mainly comprises interconnectionsbetween an optical network terminal 100, an optical module 200, anoptical fiber 101 and a network cable 103.

One end of the optical fiber 101 is connected to a remote server, andone end of the network cable 103 is connected to a local informationprocessing device. The connection between the local informationprocessing device and the remote server is realized by the connectionbetween the optical fiber 101 and the network cable 103; while theconnection between the optical fiber 101 and the network cable 103 isachieved by the optical network terminal 100 with the optical module200.

The optical fiber 101 is connected to an optical port of the opticalmodule 200, and a two-way optical-signal-connection is establishedbetween the optical module 200 and the optical fiber 101; an electricalport of the optical module 200 is connected to the optical networkterminal 100, and a two-way electrical-signal-connection is establishedbetween the optical module 200 and the optical network terminal 100; amutual conversion between optical signals and electrical signals takesplace internally within the optical module, so as to establish aninformation connection between the optical fiber and the optical networkterminal. In some embodiments of the present disclosure, an opticalsignal from an optical fiber is converted into an electrical signal bythe optical module and then input into the optical network terminal 100,and an electrical signal from the optical network terminal 100 isconverted into an optical signal by the optical module and input intothe optical fiber.

The optical network terminal has an optical module interface 102 forreceiving the optical module 200 and establishing a two-wayelectrical-signal-connection with the optical module 200; the opticalnetwork terminal has a network cable interface for receiving the networkcable 103 and establishing a two-way electrical-signal-connection withthe network cable 103; the connection between the optical module 200 andthe network cable 103 is established via the optical network terminal100. In some embodiments of the present disclosure, the optical networkterminal transmits signals from the optical module to the network cable,and transmits signals from the network cable to the optical module, andthe optical network terminal serves as the host computer of the opticalmodule to monitor the operation of the optical module.

So far, the remote server has established a two-way signal transmissionchannel with the local information processing device through the opticalfiber, the optical module, the optical network terminal and the networkcable.

A common information processing device comprises routers, switches,electronic computers, etc.; the optical network terminal is the hostcomputer of the optical module, providing data signals to the opticalmodule and receiving data signals from the optical module. A commonoptical module host computer may also be an optical line terminal, etc.

FIG. 2 is a schematic structural diagram of an optical network terminal.As shown in FIG. 2, the optical network terminal 100 includes a circuitboard 105, and a cage 106 is provided on the surface of the circuitboard 105; an electrical connector is provided inside the cage 106 forconnecting to an optical module electrical port such as a golden finger;a heat sink 107 is provided on the cage 106, and the heat sink 107 has afirst protrusion such as fins for increasing heat dissipation area.

The optical module 200 is inserted into the optical network terminal100, specifically, the electrical port of the optical module is insertedinto the electrical connector inside the cage 106, and the optical portof the optical module is connected with the optical fiber 101.

The cage 106 is located on the circuit board, and the electricalconnectors on the circuit board are wrapped in the cage; the opticalmodule 200 is inserted into the cage and is fixed by the cage, and theheat generated by the optical module 200 is conducted to the cage 106and then diffuses through the heat sink 107 on the cage.

FIG. 3 is a schematic structural diagram of an optical module accordingto an embodiment of the present disclosure, and FIG. 4 is a schematicexploded diagram of an optical module according to an embodiment of thepresent disclosure. As shown in FIG. 3 and FIG. 4, the optical module200 according to the embodiment of the present disclosure comprises anupper casing 201, a lower casing 202, an unlocking part 203, a circuitboard 300 and an optical sub-module 400.

The upper casing 201 is covered on the lower casing 202 to form awrapping cavity with two openings; the outer contour of the wrappingcavity generally presents a square shape. In some embodiments of thepresent disclosure, the lower casing 202 comprises a main board and twoside plates located on both sides of the main board and areperpendicular to the main board; the upper casing comprises a coverplate, and the cover plate covers the two side plates of the uppercasing to form a wrapping cavity; the upper casing may also comprise twoside walls located on both sides of the cover plate and areperpendicular to the cover plate, and the two side walls cooperates withthe two side plates to realize the covering of the upper casing 201 onthe lower casing 202.

One of the two openings is an electrical port 204 from which the goldenfingers of the circuit board protrude and are inserted into a hostcomputer such as an optical network terminal; the other opening is anoptical port 205, which is used to receive external optical fibers toconnect the optical sub-module 400 inside the optical module; theoptoelectronic devices such as the circuit board 300 and the opticalsub-module 400 are located in the wrapping cavity.

The assembly method of combining the upper casing and the lower casingis convenient to install the circuit board 300, the optical sub-module400 and other devices into the casing, and the upper casing and thelower casing form the outermost packaging protection casing of themodule; the upper casing and the lower casing are generally made ofmetal materials, which are intend to achieve electromagnetic shieldingand heat dissipation, so generally, the casing of the optical module arenot made into an integral part so that when assembling circuit boardsand other devices, positioning parts, heat dissipation andelectromagnetic shielding components can not to be installed, and thisis not conducive to production automation.

The unlocking part 203 is located on the outer wall of the wrappingcavity/lower casing 202, and is used to realize the fixed connectionbetween the optical module and the host computer, or to release thefixed connection between the optical module and the host computer.

The unlocking part 203 has a snap part matched with the cage of the hostcomputer; the unlocking part 203 can be moved relatively on the surfaceof the outer wall by pulling the end of the unlocking part 203; theoptical module 200 is inserted into the cage of the host computer and isfixed in the cage of the host computer by the snap part of the unlockingpart 203; by pulling the unlocking part 203, the snap part of theunlocking part 203 moves with it, thereby changes the connectionrelationship between the snap part and the host computer to release thesnapping relationship between the optical module and the host computer,so that the optical module can be pulled out from the cage of the hostcomputer.

Circuit wirings, electronic components (such as capacitors, resistors,triodes, MOS tubes) and chips (such as MCU, laser driver chip, amplitudelimiting amplifier chip, clock data recovery CDR, power management chip,data processing chip DSP), etc. are provided on the circuit board 300.

The circuit board 300 is used to provide a signal circuit for electricalconnection of the signal, and the signal circuit can provide the signal.The circuit board 300 connects the electrical devices in the opticalmodule together through circuit wirings according to the circuit design,so as to realize electrical functions such as power supply, electricalsignal transmission, and grounding.

The circuit board is generally a rigid circuit board. Due to itsrelatively hard material, the rigid circuit board can also realize thebearing function. For example, the rigid circuit board can bear the chipsecurely; when the optical transceiver components are located on thecircuit board, the rigid circuit board can also provide stable bearing;the rigid circuit board can also be inserted into the electricalconnector in the cage of the host computer. In some embodiments of thepresent disclosure, metal pins/golden fingers are formed on one endsurface of the rigid circuit board for connecting with the electricalconnector; all these are inconvenient to implement with flexible circuitboards.

Flexible circuit boards are also used in some optical modules as asupplement to rigid circuit boards; flexible circuit boards aregenerally used in conjunction with rigid circuit boards. For example,flexible circuit boards can be used to connect the rigid circuit boardswith optical transceiver components.

The light-emitting sub-module and the light-receiving sub-module may becollectively referred to as an optical sub-module. As shown in FIG. 4,the optical module according to an embodiment of the present disclosurecomprises a light-emitting sub-module and a light-receiving sub-module,the light-emitting sub-module and the light-receiving sub-module areintegrated into one optical sub-module, which means, there is integrateda light-emitting assembly and a light-receiving assembly inside theoptical sub-module 400. In some embodiments of the present disclosure,the light-emitting assembly is closer to the lower casing 202 than thelight-receiving assembly, but not limited thereto, the light-receivingassembly may also be closer to the lower casing 202 than thelight-emitting assembly.

In some embodiments of the present disclosure, the circuit board 300 canbe directly inserted into the optical sub-module 400 to be directlyelectrically connected with the light-emitting assembly and thelight-receiving assembly inside the optical sub-module 400; the opticalsub-module 400 can also be physical separated from the circuit board 300and connected to the circuit board through flexible circuit boards.

When the light-emitting assembly is closer to the lower case 202 thanthe light-receiving assembly, both the light-emitting assembly and thelight-receiving assembly are integrated in the inner cavity of theoptical sub-module 400, and the light-emitting assembly and thelight-receiving assembly are separated by a separation board, and theoptical sub-module 400 is disposed in the wrapping cavity formed by theupper casing 201 and the lower casing 202.

FIG. 5 is a schematic assembly diagram of an optical sub-module 400 anda circuit board 300 in an optical module according to an embodiment ofthe present disclosure, and FIG. 6 is an exploded schematic view of theoptical sub-module 400 and the circuit board 300 in an optical moduleaccording to an embodiment of the present disclosure. Schematic. Asshown in FIG. 5 and FIG. 6, the optical sub-module 400 comprises ahousing assembly 410, the upper surface of which comprises alight-receiving cavity and a slot that are downwardly recessedrespectively. A partition wall is provided between the light-receivingcavity and the slot, which partition wall comprises light-passing holesto communicate the light-receiving cavity with the slot; the lowersurface of the housing assembly comprises an upwardly recessedlight-emitting cavity; a separation board is formed in the middle of thehousing assembly.

The light-emitting assembly is located in the light-emitting cavity; theoptical component is located in the light-receiving cavity. Both thelight-emitting assembly and the light-receiving assembly are disposed inthe inner cavity of the housing assembly 410, the light-receivingassembly and the light-emitting assembly are stacked one above theother, and the light-receiving assembly and the light-emitting assemblyare separated by a separation board in the housing assembly 410, thelight-receiving assembly is disposed above the separation board, and thelight-emitting assembly is disposed below the separation board. One endof the circuit board 300 is inserted into the housing assembly 410, andthe light-emitting assembly and the light-receiving assembly areelectrically connected to the circuit board respectively, so that thelight-emitting assembly realizes electro-optical conversion and emitssignal light, so that the light-receiving assembly receives the signallight and realizes photoelectric conversion.

In the embodiment of the present disclosure, “above” refers to thedirection of the upper housing 201 relative to the circuit board 300,and “lower” refers to the direction of the lower housing 202 relative tothe circuit board 300. The inner cavity of the optical sub-module 400 isdivided into a light-receiving cavity and a light-emitting cavity by aseparation board, the light-receiving assembly is disposed in thelight-receiving cavity, and the light-emitting assembly is disposed inthe light-emitting cavity; a plurality of optical fiber adapters areprovided on the left side of the optical sub-module 400, thelight-emitting assembly is connected with an optical fiber adapter, andthe optical fiber adapter is used to transmit the signal light emittedby the light-emitting assembly to an external optical fiber to realizethe emission of signal light; the light-receiving assembly is connectedwith another optical fiber adapter, and the optical fiber adapter isused to transmit the signal light transmitted by the external opticalfiber into the light-receiving assembly to realize the reception of thesignal light.

Since the size of the overall outline of the optical module must conformto the interface size of the host computer, which is regulated byindustry standards, while the optical sub-module 400 is too bulky to bearranged on the circuit board 300, one end of the circuit board 300 isinserted into the housing assembly 410 to realize the electricalconnection between the optical sub-module 400 and the circuit board 300;the circuit board 300 can also be separated from the optical sub-module400, and the transfer of the electrical connection can be realizedthrough the flexible circuit board.

A light-receiving cavity and a light-receiving cover is provided in theupper part of the housing assembly 410, and the light-receiving cover iscovered on the light-receiving cavity from above; a collimating lens, anoptical multiplexing component and other devices relating tolight-receiving are provided in the light-receiving cavity. An opticalfiber adapter is provided on the left side of the housing assembly 410,and one end of the light-receiving cavity is connected to the opticalfiber adapter, and the signal light from the outside of the opticalmodule is received through the optical fiber adapter, and the receivedsignal light is transmitted to light-receiving chip through opticsdisposed in the light-receiving cavity such as the lens and the like. Anotch is provided on the side of the housing assembly 410 facing towardsthe circuit board 300, and the circuit board 300 is inserted into thehousing assembly 410 through the notch. Electrical devices such as alight-receiving chip, a transimpedance amplifier etc. located outsidethe housing assembly are provided on the surface of the circuit board300, the light beams transmitted through the optical lens such as a lensin the light-receiving cavity inject into the light-receiving chip onthe circuit board 300, and the photoelectric conversion is realized bythe light-receiving chip.

In the optical module according to an embodiment of the presentdisclosure, the light-receiving assembly in the optical sub-module 400is used to receive signal light of various wavelengths, the signal lightof different wavelengths is transmitted into the light-receiving cavitythrough the optical fiber adapter, and realizes beam splitting accordingto wavelength through the optical devices such as wavelength divisionmultiplexing components (DeMUX) in the light-receiving cavity, thesignal light after beam splitting according to wavelength is finallytransmitted to the photosensitive surface of the correspondinglight-receiving chip, and the light-receiving chip receives the signallight through its photosensitive surface. Typically, one light-receivingchip is used to receive signal light of one wavelength, thereby thelight-receiving assembly according to an embodiment of the presentdisclosure comprises a plurality of light-receiving chips to form a chiparray. For example, when the light-receiving assembly is used to receivesignal light of four different wavelengths, the light-receiving assemblycomprises four light-receiving chips for receiving the signal light offour wavelengths correspondingly; when the light-receiving assembly isused to receive the signal light of eight different wavelengths, thelight-receiving assembly comprises eight light-receiving chips forreceiving the signal light of the eight wavelengths correspondingly.

FIG. 7 is a schematic structural diagram of an optical sub-module 400 inan optical module according to an embodiment of the present disclosure.As shown in FIG. 7, two groups of light-receiving assemblies areintegrated into the optical sub-module 400 according to an embodiment ofthe present disclosure, and a first light-receiving cavity 4101 and asecond light-receiving cavity 4102 are provided in the upper part of thehousing assembly 410. The first light-receiving cavity 4101 and thesecond light-receiving cavity 4102 are disposed side by side, that is,the first light-receiving cavity 4101 and the second light-receivingcavity 4102 are sequentially disposed along the width direction of thehousing assembly 410, with the first light-receiving cavity 4101 beingarranged at one side in the width direction of the housing assembly 410,and the second light-receiving cavity 4102 being arranged at the otherside in the width direction of the housing assembly 410. A firstcollimating lens and a first wavelength division multiplexing component4201 are provided within the first light-receiving cavity 4101, and afirst optical fiber adapter 601 is provided on aside of the housingassembly 410 facing towards the optical port. The signal lighttransmitted by the first optical fiber adapter 601 is converted to acollimated beam via the first collimating lens, and the collimated beamis transmitted into the first wavelength division multiplexing component4201; the collimated beam is divided into multiple signal lights ofdifferent wavelengths by the first wavelength division multiplexingcomponent 4201. A second collimating lens and a second wavelengthdivision multiplexing component 4202 are provided in the secondlight-receiving cavity 4102, and a second optical fiber adapter 602 isprovided on the side of the housing assembly 410 facing towards theoptical port. The signal light transmitted by the second optical fiberadapter 602 is converted into a collimated beam by the secondcollimating lens, and the collimated beam is transmitted into the secondwavelength division multiplexing component 4202; the collimated beam isdivided into multiple beams of signal light of different wavelengths bythe second wavelength division multiplexing component 4202.

FIG. 8 is a working principle diagram of a DeMUX for beam splittingcomprising four wavelengths (β1, β2, β3, and β4) according to anembodiment of the present disclosure. The wavelength divisionmultiplexing component comprises a light input port for inputting signallight of multiple wavelengths on one side, and comprises a plurality oflight output ports for outputting light on the other side, each lightoutput port is used for outputting signal light of one wavelength. Forexample, as shown in FIG. 8, the signal light enters the DeMUX via thelight input port at the right end of the DeMUX; the β1 signal light isreflected six times at six different positions of the DeMUX beforereaching its light output port; the β2 signal light is reflected fourtimes at four different positions of the DeMUX before reaching its lightoutput port; the β3 signal light is reflected twice at two differentpositions of the DeMUX before reaching its light output port; the β4signal light enters the DeMUX and is then directly transmitted to itslight output port. In this way, by use of the DeMUX, signal lights ofdifferent wavelengths can enter the DeMUX through the same light inputport and output through different light output ports, thereby realizinga beam splitting of a signal light of different wavelengths. In theembodiments of the present disclosure, DeMUX is not limited to usingbeam splitting comprising four wavelength beams, and can be selectedaccording to actual needs.

FIG. 9 is a schematic structural diagram of a housing assembly 410 in anoptical module according to an embodiment of the present disclosure, andFIG. 10 is schematic structural diagram from another angle of thehousing assembly 410 in an optical module according to an embodiment ofthe present disclosure. As shown in FIG. 9 and FIG. 10, a first throughhole 4112 and a second through hole 4113 are provided on the left sidewall of the housing assembly 410, the first optical fiber adapter 601 iscommunicated with the first light-receiving cavity 4104 through thefirst through hole 4112, the first collimating lens is disposed betweenthe first through hole 4112 and the first wavelength divisionmultiplexing component 4201; the second optical fiber adapter 602 iscommunicated with the second light-receiving cavity 4102 through thesecond through hole 4113, and the second collimating lens is disposedbetween the second through hole 4113 and the second wavelength divisionmultiplexing component 4202.

The first light-receiving cavity 4101 comprises a bottom plate and aside plate surrounding the bottom plate, and the bottom plate and theside plate form a cavity structure for containing the first collimatinglens and the first wavelength division multiplexing component 4201. Afirst cover fixing glue groove 4101 a is provided on the top of the sideplate of the first light-receiving cavity 4101, thereby the first cover401 can be fixedly connected to the first light-receiving cavity 4101 byglue. In some embodiments of the present disclosure, the first coverfixing glue groove 4101 a forms a closed-loop structure on the top ofthe side plate of the first light-receiving cavity 4101, thereby theadhesive area of the first cover 401 on the top of the side plate of thefirst light-receiving cavity 4101 can be increased, ensuringsufficiently the packaging reliability of the first cover 401 and thetop of the side plate of the first light-receiving cavity 4101. In someembodiments of the present disclosure, a first repair port 4101 b isfurther provided on the top of the side plate of the firstlight-receiving cavity 4101, the first repair port 4101 b is disposed onthe top edge of the side plate of the first light-receiving cavity 4101,and communicates with the first cover fixing glue groove 4101 a. Whenthe inner devices in the first light-receiving cavity 4101 need to berepaired after the first cover 401 and the first light-receiving cavity4101 were packaged, the first cover 401 can be removed from the firstlight-receiving cavity 4101 through the first repair port 4101 b, sothat the first cover 401 can be removed without damaging the first cover401 or the first light-receiving cavity 4101, thereby reducing thedifficulty and cost of repairing.

Similarly, the second light-receiving cavity 4102 comprises a bottomplate and a side plate surrounding the bottom plate, and the bottomplate and the side plate form a cavity structure for containing thesecond collimating lens and the second wavelength division multiplexingcomponent 4202. A second cover fixing glue groove 4102 a is provided onthe top of the side plate of the second light-receiving cavity 4102,thereby the second cover 402 can be fixedly connected to the secondlight-receiving cavity 4102 by glue. In some embodiments of the presentdisclosure, the second cover fixing glue groove 4102 a forms aclosed-loop structure on the top of the side plate of the secondlight-receiving cavity 4102, thereby the adhesive area of the secondcover 402 on the top of the side plate of the second light-receivingcavity 4102 can be increased, ensuring sufficiently the packagingreliability of the second cover 402 and the top of the side plate of thesecond light-receiving cavity 4102. In some embodiments of the presentdisclosure, a second repair port 4102 b is further provided on the topof the side plate of the second light-receiving cavity 4102, the secondrepair port 4102 b is disposed on the top edge of the side plate of thesecond light-receiving cavity 4102, and communicates with the secondcover fixing glue groove 4102 a. When the inner devices in the secondlight-receiving cavity 4102 need to be repaired after the second cover402 and the second light-receiving cavity 4102 were packaged, the secondcover 402 can be removed from the second light-receiving cavity 4102through the second repair port 4102 b, so that the second cover 402 canbe removed without damaging the second cover 402 or the secondlight-receiving cavity 4102, thereby reducing the difficulty and cost ofrepairing.

In some embodiments, a first DeMUX fixing glue groove 4108 is providedon the bottom plate of the first light-receiving cavity 4101, and thefirst DeMUX fixing glue groove 4108 is used to hold dispensing glue. Forexample, when the first wavelength division multiplexing component 4201needs to be fixed, glue is dispensed into the first DeMUX fixing gluegroove 4108, and then the first wavelength division multiplexingcomponent 4201 is installed and placed on the first DeMUX fixing gluegroove 4108; after the glue is solidified, a fixing of the firstwavelength division multiplexing component 4201 on the bottom plate isrealized. Similarly, the second DeMUX fixing glue groove 4110 is used tohold the dispensing glue. For example, when the second wavelengthdivision multiplexing component 4202 needs to be fixed, glue isdispensed into the second DeMUX fixing glue groove 4110, and then thesecond wavelength division multiplexing component 4202 is installed andplaced on the second DeMUX fixing glue groove 4110; after the glue issolidified, a fixing of the second wavelength division multiplexingcomponent 4202 on the bottom plate is realized.

The DeMUX fixing glue groove formed on the bottom surface of thelight-receiving cavity has an annular, protuberant circumference. Thecircumference is of a closed shape, so that the glue groove is delimitedby the closed circumference. The wavelength division multiplexingcomponent is disposed onto the annular, protruded circumference. Glue isprovided into the groove enclosed by the annular, protuberantcircumference for adhering the wavelength division multiplexingcomponent.

In the embodiments of the present disclosure, a first slot 4103 and asecond slot 4104 are provided on the side of the housing assembly 410facing towards the circuit board 300, and the first slot 4103 and thesecond slot 4104 are sequentially disposed along the width direction ofthe housing assembly 410, wherein both the upper side and right side ofthe first slot 4103 and the second slot 4104 are open, with the firstslot 4103 and the second slot 4104 being separated by the separationboard 4111. A first light-receiving assembly 430 is provided inside ofthe first slot 4103, and a second light-receiving assembly 440 isprovided inside the second slot 4104. Taking the receiving of light ofeight wavelengths comprising two wavelength bands as an example, asingle wavelength band comprises light of four wavelengths, wherein, thesignal light transmitted by the first optical fiber adapter 601 isconverted into a collimated beam through the first collimating lens, andthe collimated beam then demultiplexes a collimated beam into four beamsof different wavelengths via the first wavelength division multiplexingcomponent 4201, the four beams of different wavelengths are respectivelytransmitted to the first light-receiving assembly 430, and the firstlight-receiving assembly 430 realizes the photoelectric conversion; thesignal light transmitted by the second optical fiber adapter 402 isconverted into a collimated beam through the second collimating lens,and the collimated beam then demultiplexes a collimated beam into fourbeams of different wavelengths via the second wavelength divisionmultiplexing component 4202, the four beams of different wavelengths arerespectively transmitted to the second light-receiving assembly 440, andphotoelectric conversion is realized by the second light-receivingassembly 440.

FIG. 11 is a partial cross-sectional view of a housing assembly 410 inan optical module according to an embodiment of the present disclosure.As shown in FIG. 11, the first light-receiving cavity 4101 and the firstslot 4103 may be communicated through light-passing holes 4109; that is,the first light-receiving cavity 4101 and the first slot 4103 areseparated by a partition wall, with a plurality of light-passing holes4109 being provided in the partition wall; the multiple beams ofdifferent wavelengths demultiplexed and output through the firstwavelength division multiplexing component 4201 in the firstlight-receiving cavity 4101 are transmitted to the first light-receivingassembly 430 via the corresponding light-passing holes 4109. Similarly,the second light-receiving cavity 4102 and the second slot 4104 may becommunicated through the light-passing holes, that is, the secondlight-receiving cavity 4102 and the second slot 4104 are separated bythe partition wall provided with the light-passing holes 4109; themultiple beams of different wavelengths demultiplexed and output throughthe second wavelength division multiplexing component 42012 in thesecond light-receiving cavity 4102 are transmitted to the secondlight-receiving assembly 440 via the corresponding light-passing holes4109.

In the embodiments of the present disclosure, the first wavelengthdivision multiplexing component 4201 is used to demultiplex one beaminto four beams of different wavelengths. Therefore, four light-passingholes 4109 are provided between the first light-receiving cavity 4101and the first slot 4103, the four light-passing holes 4109 aresequentially disposed along the width direction of the housing assembly410, and the four light output ports of the first wavelength divisionmultiplexing component 4201 are disposed in one-to-one correspondencewith the four light-passing holes 4109, so that the four beams ofdifferent wavelengths demultiplexed and output from the first wavelengthdivision multiplexing component 4201 are respectively transmitted to thefirst light-receiving assembly 430 through the correspondinglight-passing holes 4109. Similarly, the second wavelength divisionmultiplexing component 4202 is used to demultiplex one beam into fourbeams of different wavelengths. Therefore, four light-passing holes 4109are provided between the second light-receiving cavity 4102 and thesecond slot 4104, the four light-passing holes 4109 are sequentiallydisposed along the width direction of the housing assembly 410, and thefour light output ports of the second wavelength division multiplexingcomponent 4202 are disposed in one-to-one correspondence with the fourlight-passing holes 4109, so that the four beams of differentwavelengths demultiplexed and output from the second wavelength divisionmultiplexing component 4202 are respectively transmitted to the secondlight-receiving assembly 440 through the corresponding light-passingholes 4109.

In the embodiments of the present disclosure, the first light-receivingcavity 4101 and the first slot 4103 can also be directly communicatedinto an integrated cavity, and a first collimating lens and the firstwavelength division multiplexing component 4201 are provided on the sideof the integrated cavity close to the first optical fiber adapter 601,the first light-receiving assembly 430 is disposed on the side of theintegrated cavity close to the circuit board 300, so that the signallight transmitted by the first optical fiber adapter 601 is converted tocollimated beam through the first collimating lens, the collimated beamis demultiplexed into four beams with different wavelengths via thefirst wavelength division multiplexing component 4201, and the fourbeams of different wavelengths are directly transmitted to the firstlight-receiving assembly 430. Similarly, the second light-receivingcavity 4102 and the second slot 4104 can also be directly communicatedinto an integrated cavity, and a second collimating lens and the secondwavelength division multiplexing component 4202 are provided on the sideof the integrated cavity close to the second optical fiber adapter 602,the second light-receiving assembly 440 is disposed on the side of theintegrated cavity close to the circuit board 300, so that the signallight transmitted by the second optical fiber adapter 602 is convertedto collimated beam through the second collimating lens, the collimatedbeam is demultiplexed into four beams with different wavelengths via thesecond wavelength division multiplexing component 4202, and the fourbeams of different wavelengths are directly transmitted to the secondlight-receiving assembly 440.

Compared with communicating the first light-receiving cavity 4101 andthe first slot 4103 into an integrated cavity, the way of the firstlight-receiving cavity 4101 communicating with the first slot 4103through the light-passing hole 4109 can reduce the processing of thehousing assembly 410, and the structure of the housing assembly 410 ismore retained, so that the heat generated by the optoelectronic devicesof the light-receiving assembly and the optoelectronic devices of thelight-emitting assembly is conducted to the upper housing 201 and thelower housing 202 through where has no drilling on the housing assembly410, therefore increasing the heat dissipation efficiency of the opticalsub-module 400.

FIG. 12 is a schematic structural diagram of a light-receiving assemblyin an optical sub-module 400 in an optical module according to anembodiment of the present disclosure, and FIG. 13 is a schematic diagramof an optical path of a light-receiving assembly in the opticalsub-module 400 in an optical module according to an embodiment of thepresent disclosure Schematic. As shown in FIG. 12 and FIG. 13, the firstlight-receiving assembly 430 and the second light-receiving assembly 440respectively comprise several light-receiving chips, which are PDs(photodetectors), such as APDs (avalanche diodes), for converting thereceived signal light into photocurrent. In some embodiments of thepresent disclosure, the light-receiving chips in the firstlight-receiving assembly 430 and the second light-receiving assembly 440are respectively disposed on the surface of the metallized ceramic whichforms a circuit pattern that can supply power to the light-receivingchip. Then, the metallized ceramic provided with the light-receivingchip is applied on the circuit board 300, or the light-receiving chip isapplied on the flexible circuit board which is electrically connectedwith the circuit board 300.

In the embodiments of the present disclosure, the first light-receivingassembly 430 and the second light-receiving assembly 440 furthercomprise transimpedance amplifiers, respectively, the transimpedanceamplifiers are directly applied on the circuit board 300, are connectedto the corresponding light-receiving chips, and receive the currentsignal generated by the light-receiving chip and convert the receivedcurrent signal into a voltage signal. In some embodiments of the presentdisclosure, the transimpedance amplifiers are connected to thecorresponding light-receiving chip by means of wire adhering, such as asemiconductor gold wire adhering (Gold Wire Bonding).

In some embodiments of the present disclosure, the first light-receivingassembly 430 comprises a first ceramic substrate 4304 and a firsttransimpedance amplifier 4305. The first transimpedance amplifier 4305is placed on one side of the first ceramic substrate 4304, as shown inFIG. 13, the first transimpedance amplifier 4305 is located on the rightside of the first ceramic substrate 4304. Wherein, four firstlight-receiving chips 4303 are provided on the first ceramic substrate4304, and the first ceramic substrate 4304 is connected to the firsttransimpedance amplifier 4305 by wire adhering, so as to achieve theconnection of the first light-receiving chip 4303 and the firsttransimpedance amplifier 4305. The longer the length of the wireadhering is, the larger the inductance generated by the wire adheringwill be, and the signal mismatch will also be larger, while the signaloutput from the first light-receiving chip 4303 is a small signal, whichwill in turn cause the signal quality to deteriorate. Therefore, thefirst light-receiving chip 4303 and the first transimpedance amplifier4305 are disposed as close as possible to reduce the length of the wireadhering and ensure the signal transmission quality, and then the firsttransimpedance amplifier 4305 is disposed on one side of the firstceramic substrate 4304 to cause the first ceramic substrate 4304 bedisposed as close to the transimpedance amplifier 4305 as possible.

In the embodiments of the present disclosure, the first ceramicsubstrate 4304 is also used to elevate the first light-receiving chip4303, so that the electrodes of the first light-receiving chip 4303 andthe pins on the first transimpedance amplifier 4305 are on the sameplane, ensuring that the wire adhering between the first light-receivingchip 4303 and the first transimpedance amplifier 4305 is the shortest.

Similarly, the second light-receiving assembly 440 comprises a secondceramic substrate 4404 and a second transimpedance amplifier 4405. Thesecond transimpedance amplifier 4305 is placed on one side of the secondceramic substrate 4404, that is, the second transimpedance amplifier4405 is located on the right side of the second ceramic substrate 4404.Wherein, four second light-receiving chips 4403 are provided on thesecond ceramic substrate 4404, and the second ceramic substrate 4404 isconnected to the second transimpedance amplifier 4405 by wire adhering,so as to achieve the connection of the second light-receiving chip 4403and the second transimpedance amplifier 4405. The longer the length ofthe wire adhering is, the larger the inductance generated by the wireadhering will be, and the signal mismatch will also be larger, while thesignal output from the second light-receiving chip 4403 is a smallsignal, which will in turn causes the signal quality to deteriorate.Therefore, the second light-receiving chip 4403 and the secondtransimpedance amplifier 4405 are disposed as close as possible toreduce the length of the wire adhering and ensure the signaltransmission quality, and then the second transimpedance amplifier 4405is disposed on one side of the second ceramic substrate 4404 to causethe second ceramic substrate 4404 be disposed as close to thetransimpedance amplifier 4405 as possible.

In the embodiments of the present disclosure, the second ceramicsubstrate 4404 is also used to elevate the second light-receiving chip4403, so that the electrodes of the second light-receiving chip 4403 andthe pins on the second transimpedance amplifier 4405 are on the sameplane, ensuring that the adhering wire between the secondlight-receiving chip 4403 and the second transimpedance amplifier 4405is the shortest.

In the embodiments of the present disclosure, if the pins of thetransimpedance amplifier are sufficient, the first transimpedanceamplifier 4305 and the second transimpedance amplifier 4405 can use onetransimpedance amplifier chip, and furthermore, four firstlight-receiving chips 4303 and four second light-receiving chip 4403 maybe disposed on one ceramic substrate.

In order to facilitate the light-receiving chip to receive the signallight, the first light-receiving assembly 430 further comprises a firstlens assembly 4301, and the first lens assembly 4301 is used to adjustthe optical path in the process of transmitting the four beams ofdifferent wavelengths output from the first wavelength divisionmultiplexing component 4201 to the first light-receiving assembly 430;the second light-receiving assembly 440 further comprises a second lensassembly 4401, and the second lens assembly 4401 is used to adjust theoptical path in the process of transmitting the four beams of differentwavelengths output from the second wavelength division multiplexingcomponent 4202 to the second light-receiving assembly 440.

In the embodiments of the present disclosure, the optical axis of thefirst lens assembly 4301 is parallel to the bottom surface of the firstslot 4103, while the photosensitive surface of the first light-receivingchip 4301 is also parallel to the bottom surface of the first slot 4103,but the first light receiving chip 4301 is disposed on the upper surfaceof the circuit board 300, and there is a latitude difference between thebottom surface of the first slot 4103 and the upper surface of thecircuit board 300. Therefore, in order to ensure that the firstlight-receiving chip 4301 receives the signal light normally, the firstlight-receiving assembly 430 further comprises a first reflective mirror4302, the first reflective mirror 4302 is disposed above the firstceramic substrate 4304 and covers the four first light-receiving chips4303 disposed on the first ceramic substrate 4304, changing thedirection of the optical axis of the signal light emitted by the firstlens assembly 4301 by means of the reflective surface of the firstreflective mirror 4302, so that the optical axis of the signal lightemitted by the first lens assembly 4301 is converted from a bottomsurface parallel to the first slot 4103 to a bottom surfaceperpendicular to the first slot 4103, so that the signal light isvertically incident onto the photosensitive surface corresponding to thefirst light-receiving chip 4303.

The signal light transmitted to the first light-receiving cavity 4101via the first optical fiber adapter 601 is converted into a collimatedbeam after passing through the first collimating lens, and thecollimated beam is incident into the first wavelength divisionmultiplexing component 4201, a collimated beam is demultiplexed intofour beams of different wavelengths via the second wave demultiplexingcomponent 4201, and the four beams of different wavelengths aretransmitted to the first slot 4103 through the corresponding light holes4109, respectively, are focused via the corresponding lenses, and thentransmitted to the first reflective mirror 4302. When the four beams ofdifferent wavelengths are transmitted to the reflective surface of thefirst reflective mirror 4302, they are reflected by the reflectivesurface of the first reflective mirror 4302, so that the transmissiondirection of the light beam is changed from the direction parallel tothe bottom surface of the first slot 4103 to the direction perpendicularto the bottom surface of the first slot 4302, and the four beams arerespectively transmitted to the corresponding first light-receiving chip4303 on the first ceramic substrate 4304 below the reflective surface ofthe first reflective mirror 4302 after the direction changing,photoelectric conversion is realized by the first light-receiving chip4303.

Similarly, the optical axis of the second lens assembly 4401 is parallelto the bottom surface of the second slot 4104, while the photosensitivesurface of the second light-receiving chip 4401 is also parallel to thebottom surface of the second slot 4104, but the second light receivingchip 4401 is disposed on the upper surface of the circuit board 300, andthere is a height difference between the bottom surface of the secondslot 4104 and the upper surface of the circuit board 300. Therefore, inorder to ensure that the second light-receiving chip 4401 receives thesignal light normally, the second light-receiving assembly 440 comprisesa second reflective mirror 4402, the second reflective mirror 4402 isdisposed above the second ceramic substrate 4404 and covers the foursecond light-receiving chips 44303 disposed on the second ceramicsubstrate 4404, changing the direction of the optical axis of the signallight emitted by the second lens assembly 4401 by means of thereflective surface of the second reflective mirror 4402, so that theoptical axis of the signal light emitted by the second lens assembly4401 is converted from a bottom surface parallel to the second slot 4104to a bottom surface perpendicular to the second slot 4104, so that thesignal light is vertically incident onto the photosensitive surfacecorresponding to the second light-receiving chip 4403

FIG. 14 is a cross-sectional view of the second light-receiving assembly440 in the housing assembly 410 in an optical module according to anembodiment of the present disclosure, and FIG. 15 is an assemblycross-sectional view of a second light-receiving assembly 440, a housingassembly 410 and a circuit board 300 in an optical module according toan embodiment of the present disclosure. As shown in FIG. 14 and FIG.15, the signal light transmitted to the second light-receiving cavity4102 via the second optical fiber adapter 602 is converted into acollimated beam after passing through the first collimating lens, andthe collimated beam is incident into the second wavelength divisionmultiplexing component 4202, a collimated beam is demultiplexed intofour beams of different wavelengths via the second wave demultiplexingcomponent 4202, and the four beams of different wavelengths aretransmitted to the corresponding lenses of the second lens assembly 4401in the second slot 4104 through the corresponding light holes 4109,respectively, are focused via the corresponding lenses, and thentransmitted to the second reflective mirror 4402. When the four beams ofdifferent wavelengths are transmitted to the reflective surface of thesecond reflective mirror 4402, they are reflected by the reflectivesurface of the second reflective mirror 4402, so that the transmissiondirection of the light beam is changed from the direction parallel tothe bottom surface of the second slot 4104 to the directionperpendicular to the bottom surface of the second slot 4402, and thefour beams are respectively transmitted to the corresponding secondlight-receiving chip 4402 on the second ceramic substrate 4404 below thereflective surface of the second reflective mirror 4403 after thedirection changing, photoelectric conversion is realized by the secondlight-receiving chip 4403.

In the embodiments of the present disclosure, the first reflectivemirror 4302 and the second reflective mirror 4402 are both 45°reflective mirrors, that is, the first reflective mirror 4302 and thesecond reflective mirror 4402 respectively comprise a 45° reflectionsurface, with the 45° reflective surface of the first reflective mirror4302 capping the four first light-receiving chips 4303 provided on thefirst ceramic substrate 4304, and the 45° reflective surface of thesecond mirror 4402 capping the four second light-receiving chips 4403provided on the second ceramic substrate 4404.

Since the first slot 4103 and the second slot 4104 are slots openedupwardly, in order to protect the first lens assembly 4301 and the firstreflective mirror 4302 in the first slot 4103 as well as the second lensassembly 4401 and the second reflective mirror 4403 in the second slot4104, the first slot 4103 and the second slot 4104 are covered with acovering hood 500, wherein the left side and the lower side of thecovering hood 500 are both open, the left side of the covering hood 500is connected with the partition wall of the housing, and the opening atthe lower side of the covering hood 500 is in contact with an uppersurface of the circuit board.

After the first lens assembly 4301 and the first reflective mirror 4302is installed in the first slot 4103 according to the optical path of thefirst light-receiving assembly 430, and the second lens assembly 4401and the second reflective mirror 4402 is installed in the second slot4104 according to the light path of the second light-receiving assembly440, the covering hood 500 is covered onto the first slot 4103, thesecond slot 4104 and the light-receiving chips; the lower opening of thecovering hood 500 is in contact with the upper surface of the circuitboard 300. The upper surface and two side surfaces in the widthdirection of the covering hood 500 are respectively in the same planesas the upper surface, two side surfaces in the width direction of thehousing assembly 410, so that the first slot 4103 and the second slot4104 cooperate with the covering hood 500 to form cavities for placingthe first light-receiving assembly 430 and the second light-receivingassembly 440.

A first notch 4114 is provided at the side of the housing assembly 410approximate to the circuit board 300; the first notch 4114 is locatedunderneath the first slot 4103 and the second slot 4104, and the bottomsurface of the first notch 4114 is parallel to the bottom surfaces ofthe first slot 4103 and the second slot 4104, so that when one end ofthe circuit board 300 is inserted into the first notch 4114, thesurfaces of the circuit board 300 are parallel to the bottom surfaces ofthe first slot 4103 and the second slot 4104, and the first ceramicsubstrate 4304, the first transimpedance amplifier 4305, the secondceramic substrate 4404 and the second transimpedance amplifier 4405provided on the circuit board 300 are also parallel to the bottomsurfaces of the first slot 4103 and the second slot 4104; by this, thebeam focused by the first lens assembly 4301 may be reflected by thefirst reflective mirror 4302 to the corresponding first light-receivingchip 4303 on the first ceramic substrate 4304, and the beam focused bythe second lens assembly 4401 may be reflected by the second reflectivemirror 4402 to the corresponding second light-receiving chip 4403 on thesecond ceramic substrate 4404.

A second notch is provided between the first notch 4114 and the bottomsurfaces of the first slot 4103 and the second slot 4104, the lower sideof the second notch being in communication with the first notch 4114,and the right side of the second notch is opened; an aluminum nitrideceramic substrate 800 is provided in the second notch, with the aluminumnitride ceramic substrate 800 being in contact with the inner walls ofthe second notch and the upper surface of the circuit board 300,respectively. In some embodiments of the present disclosure, an uppersurface of the aluminum nitride ceramic substrate 800 is in contact withan upper sidewall of the second notch, while a lower surface of thealuminum nitride ceramic substrate 800 is in contact with the uppersurface of the circuit board 300, and gaps between the aluminum nitrideceramic substrate 800 and housing assembly 410 as well as gaps betweenthe aluminum nitride ceramic substrate 800 and the circuit board 300 arefilled with insulating high thermal conductivity glue. As shown in theheat conduction path, the heat generated by the first light-receivingchip 4303 is conducted to the circuit board 300 through the firstceramic substrate 4304, the heat generated by the first transimpedanceamplifier 4305 is directly conducted to the circuit board 300; the heatgenerated by the second light-receiving chip 4403 is conducted to thecircuit board 300 through the second ceramic substrate 4404, the heatgenerated by the second transimpedance amplifier 4405 is directlyconducted to the circuit board 300; meanwhile, the heat conducted to thecircuit board 300 is conducted to housing assembly 410 through thecopper cladding on the circuit board 300 and the aluminum nitrideceramic substrate 800, and then conducted to the upper casing 201 andthe lower casing 202 of the optical module through the housing assembly410 for heat dissipation, which improves heat dissipation efficiency ofthe light-receiving assembly integrated in the optical sub-module 400.

The first transimpedance amplifier 4305 and the second transimpedanceamplifier 4405 are provided on the circuit board 300; the firsttransimpedance amplifier 4305 may also be arranged on a heat sink, andthen the heat sink is provided on the upper surface of the circuit board300, so that the heat sink can not only conduct the heat generated bythe first transimpedance amplifier 4305 to the circuit board 300, butalso elevate the first transimpedance amplifier 4305, so that the firsttransimpedance amplifier 4305 and the first light-receiving chip 4303may be located on the same plane/in the same level. Similarly, thesecond transimpedance amplifier 4405 can also be arranged on a heatsink, and then the heat sink can be provided on the upper surface of thecircuit board 300, so that the heat sink can not only conduct the heatgenerated by the second transimpedance amplifier 4405 to the circuitboard 300, but also elevate the second transimpedance amplifier 4405, sothat the second transimpedance amplifier 4405 and the secondlight-receiving chip 4403 may be located on the same plane/in the samelevel.

In the embodiments of the present disclosure, the optical sub-module 400includes both a light-receiving assembly and a light-emitting assembly,with the light-receiving assembly and the light-emitting assembly beingseparated by a separation board; the light-receiving assembly isintegrated above the separation board, and the light-emitting assemblyis integrated below the separation board.

FIG. 16 is a schematic assembly diagram from another angle of view forthe circuit board 300 and the optical sub-module 400 in an opticalmodule according to an embodiment of the present disclosure, FIG. 17 isa schematic assembly diagram from a further angle of view for thecircuit board 300 and the optical sub-module 400 in an optical moduleaccording to an embodiment of the present disclosure, and FIG. 18 is aschematic partial exploded diagram of the circuit board 300 and theoptical sub-module 400 in an optical module according to an embodimentof the present disclosure. As shown in FIG. 16, FIG. 17, and FIG. 18, alight-emitting cavity and a light-emitting cover 403 are provided at thelower portion of the housing assembly 410, wherein the light-emittingcover 403 covers the light-emitting cavity from below, and photoelectricdevices related to light-emitting, such as lenses and light-emittingchips, are provided within the light-emitting cavity. The first notch4114 is provided at the side of the housing assembly 410 facing towardsthe circuit board 300, the circuit board 300 is inserted into thehousing assembly 410 through the first notch 4114, a pad is provided onthe lower surface of the circuit board, and the light-emitting assemblyis connected to the pad through wires, so that the electrical devicessuch as light-emitting chips disposed within the light-emitting cavityare electrically connected with the circuit board 300 to drive thelight-emitting chip so as to realize electro-optical conversion.

In the optical module provided by the embodiments of the presentdisclosure, the light-emitting assembly in the optical sub-module 400 isused to emit signal lights of multiple different wavelengths, and thesignal lights of different wavelengths achieve light multiplexingthrough optics such as a wavelength division multiplexing component(MUX) in the light-emitting cavity, and the combined, multiplexed lightbeam is transmitted to the external optical fiber through the opticalfiber adapter to realize an emission of signal light. Typically, onelight-emitting chip is used to emit signal light of one wavelength, andthe light-emitting assembly according to the embodiment of the presentdisclosure comprises a plurality of light-emitting chips to form a chiparray. For example, when the light-emitting assembly is used to emitsignal lights of four different wavelengths, the light-emitting assemblycomprises four light-emitting chips for correspondingly emitting signallights of four different wavelengths; when the light-emitting assemblyis used to emit signal lights of eight different wavelengths, thelight-emitting assembly comprises eight light-emitting chips forcorrespondingly emitting signal lights of eight wavelengths.

FIG. 19 is another schematic structural diagram of a housing assembly410 in an optical module according to an embodiment of the presentdisclosure. As shown in FIG. 19, in the light-emitting assembly in theoptical sub-module 400, the light-emitting cavity 4115houses/accommodates optical devices such as the wavelength divisionmultiplexing component 460, and the light beams of multiple differentwavelengths emitted by the light-emitting chips are transmitted to thewavelength division multiplexing component 460, which multiplexes lightbeams of multiple different wavelengths into a composite, multiplexedlight beam which is transmitted into an external optical fiber throughan optical fiber adapter.

In the embodiments of the present disclosure, four light input ports forincident signal lights of multiple wavelengths are provided the on theright side of the wavelength division multiplexing component 460, andone light output port for emitting light is provided on the left side;each light input port is used for incident signal light of onewavelength. In some embodiments of the present disclosure, signal lightsof multiple different wavelengths enter the wavelength divisionmultiplexing component 460 through corresponding light input ports,wherein one beam of signal light is reflected six times at six differentpositions of the wavelength division multiplexing component 460 beforereaching the light output port, one beam of signal light is reflectedfour times at four different positions of the wavelength divisionmultiplexing component 460 before reaching the light output port, onebeam of signal light is reflected twice at two different positions ofthe wavelength division multiplexing component 460 before reaching thelight output port, and one beam of signal light is incident onto thewavelength division multiplexing component 460 and then directlytransmitted to the light output port. In this way, the wavelengthdivision multiplexing component realizes that signal lights of differentwavelengths enter the wavelength division multiplexing component viadifferent light input ports, and are output via the same light outputport, thereby obtaining a beam consisted of signal lights of differentwavelengths. In the embodiments of the present disclosure, thewavelength division multiplexing component is not limited to a beammultiplexing of four wavelengths, and can be designed according toactual needs.

Two groups of light-emitting assemblies are integrated in the opticalsub-module 400 according to an embodiment of the present disclosure, anda light-emitting cavity 4115 is provided in the lower part of thehousing assembly 410, converging lens, wavelength division multiplexingcomponents 460, and light-emitting assemblies are provided in thelight-emitting cavity 4115; an optical fiber adapter is provided on theleft side of the housing assembly 410, and the optical fiber adapter iscommunicated with the light-emitting cavity 4115. The wavelengthdivision multiplexing component 460 is disposed at a side of thelight-emitting cavity 4115 approximate to the optical fiber adapter, thelight-emitting assembly is disposed at a side of the light-emittingcavity 4115 close to the circuit board 300, and the converging lens isdisposed between the optical fiber adapter and the wavelength divisionmultiplexing component 460. Signal lights of multiple differentwavelengths emitted by the light-emitting assembly are therebytransmitted to the wavelength division multiplexing component 460, themultiple light beams of different wavelengths are multiplexed into acomposite, multiplexed light beam via the wavelength divisionmultiplexing component 460, and the multiplexed light beam is coupled tothe optical fiber adapter via the converging lens, thereby realizing anemission of lights of multiple different wavelengths.

FIG. 20 is a schematic structural diagram of a light-emitting assemblyin an optical sub-module 400 in an optical module according to anembodiment of the present disclosure, and FIG. 21 is a schematic diagramof an optical path of the light-emitting assembly in an optical moduleaccording to an embodiment of the present disclosure. As shown in FIG.20 and FIG. 21, the light-emitting cavity 4115 comprises a top plateprovided at the top of the cavity and side plates surrounding the topplate. The top plate and the side plates form a cavity structure foraccommodating the wavelength division multiplexing component 460 and thelight transmitting components. The light transmitting componentscomprises a first light-emitting assembly 470 and a secondlight-emitting assembly 480 that are provided at the side of thelight-emitting cavity 4115 approximate to the circuit board 300, and areelectrically connected to the circuit boards 300, respectively. Thewavelength division multiplexing component 460 provided in thelight-emitting cavity 4115 comprises a first wavelength divisionmultiplexing component 4601 and a second wavelength divisionmultiplexing component 4602, and a third optical fiber adapter 603 and afourth optical fiber adapter 604 is provided at the left side of thehousing assembly 410; the third optical fiber adapter 603 extends intothe light-emitting cavity 4115, and a first convergence lens 701 isprovided between the third optical fiber adapter 603 and the firstwavelength division multiplexing component 4601; a second converginglens 702 is provided between the fourth optical fiber adapter 604 andthe second wavelength division multiplexing components 4602. In thisway, signal lights of four different wavelengths emitted by the firstlight-emitting assembly 470 are transmitted to the first wavelengthdivision multiplexing component 4601, and the four beams of signal lightof different wavelengths are multiplexed into a composite, multiplexedbeam via the first wavelength division multiplexing component 4601; themultiplexed light beam is converged and coupled to the third opticalfiber adapter 603 via the first converging lens 701. Similarly, signallights of four different wavelengths emitted by the secondlight-emitting assembly 480 are transmitted to the second wavelengthdivision multiplexing component 4602, and the four beams of signal lightof different wavelengths are multiplexed into a composite, multiplexedbeam via the second wavelength division multiplexing component 4602; thecomposite light beam is converged and coupled to the fourth opticalfiber adapter 604 via the second converging lens 702.

The first optical fiber adapter and the third optical fiber adapter areprovided at different levels. The second optical fiber adapter and thefourth optical fiber adapter are provided at different levels.

In the embodiments of the present disclosure, the first light-emittingassembly 470 and the second light-emitting assembly 480 comprise aplurality of light-emitting chips, respectively, and the light-emittingchips are laser chips for converting a current signal into laser lightfor emission. In some embodiments of the present disclosure, the firstlight-emitting assembly 470 comprises a third lens assembly 4701 and afirst laser assembly 4702 for emitting multiple signal light beams ofdifferent wavelengths; the third lens assembly 4701 is provided in alight emission direction from the first laser assembly 4702 forconverting the beam emitted by the first laser assembly 4702 into acollimated beam; the first wavelength division multiplexing component4601 is disposed in a light emission direction from the third lensassembly 4701 for multiplexing multiple beams of different wavelengthsinto a composite, multiplexed beam; the first converging lens 701 isdisposed in the light emission direction from the first wavelengthdivision multiplexing component 4601, in order that a multiplexed beamemitted by the first wavelength division multiplexing component 4601 maybe converged and coupled into the third fiber adapter 603 for emission.

Similarly, the second light-emitting assembly 480 comprises a fourthlens assembly 4801 and a second laser assembly 4802 for emittingmultiple signal light beams of different wavelengths, and the fourthlens assembly 4801 is provided in the light emission direction from thesecond laser assembly 4802 for converting the beam emitted by the secondlaser assembly 4802 into a collimated beam; the second wavelengthdivision multiplexing component 4602 is disposed in the light emissiondirection from the fourth lens assembly 4801 for multiplexing multiplebeams of different wavelengths into a composite, multiplexed beam; thesecond converging lens 702 is disposed in the light emission directionfrom the second wavelength division multiplexing component 4602, inorder that the multiplexed beam emitted by the second wavelengthdivision multiplexing component 4601 is converged and coupled into thefourth fiber adapter 604 for emission.

In the embodiments of the present disclosure, the first laser assembly4702 may comprise four lasers, the third lens assembly 4701 may comprisefour collimating lenses, with the four lasers being provided in aone-to-one correspondence with the four collimating lenses, such thatthe four lasers emit four beams of different wavelengths, respectively,which are respectively transmitted to the corresponding collimatinglenses. Correspondingly, the second laser assembly 4802 may comprisefour lasers, the fourth lens assembly 4801 may comprise four collimatinglenses, with the four lasers being provided in a one-to-onecorrespondence with the four collimating lenses, such that the fourlasers emit four beams of different wavelengths, respectively, which arerespectively transmitted to the corresponding collimating lenses.

The first wavelength division multiplexing component 4601 and the secondwavelength division multiplexing component 4602 both comprise four inputchannels; the four collimated light beams output from the fourcollimating lenses of the third lens assembly 4701 enter the four inputchannels of the first wavelength division multiplexing component 4601,respectively. The first wavelength division multiplexing component 4601converts the collimated beams of the four channels into a composite,multiplexed beam that is converged and coupled to the third fiberadapter 603 through the first converging lens 701, so as to achieve anemission of a 4-channel wavelength division multiplexed light.Similarly, the four collimated light beams output from the fourcollimating lenses of the fourth lens assembly 4702 enter the four inputchannels of the second wavelength division multiplexing component 4602,respectively. The second wavelength division multiplexing component 4602converts the collimated beams of the four channels into a composite,multiplexed beam that is converged and coupled to the fourth fiberadapter 604 through the second converging lens 702, so as to achieve anemission of a 4-channel wavelength division multiplexed light. In thisway, the present disclosure multiplexes the 8-channel light beams intotwo composite, multiplexed light beams through two wavelength divisionmultiplexing components and couples the two multiplexed light beams intothe two optical fiber adapters respectively, thereby reducing the volumeoccupied by the light-emitting assembly in the optical module, which isadvantageous for a miniaturization of optical modules.

In the embodiments of the present disclosure, in order to realize theemission optical path of the above-mentioned embodiment, it is necessaryto provide a platform for device supporting and coupling for the firstlight-emitting assembly 470, the first wavelength division multiplexingcomponent 4601, the second light-emitting assembly 480 and the secondwavelength division multiplexing component 4602, so as to realize apassive coupling of the first light-emitting assembly 470 with the firstwavelength division multiplexing component 4601 as well as a passivecoupling of the second light-emitting assembly 480 with the secondwavelength division multiplexing component 4602, thus reduce a couplingdifficulty of the emission optical path.

FIG. 22 is a schematic structural diagram from another angle of view fora housing assembly 410 in an optical module according to an embodimentof the present disclosure. As shown in FIG. 22, a first top surface 4115c and a second top surface 4116 are formed on the top plate of thelight-emitting cavity 4115 that is formed in the lower part of thehousing assembly 410, and a step is formed between the first top surface4115 c and the second top surface 4116, that is, there is a heightdifference between the first top surface 4115 c and the second topsurface 4116, and the second top surface 4116 is positioned at a levelhigher than the first top surface 4115 c. A first MUX fixing glue groove4117 and a second MUX fixing glue groove 4118 are provided on the firsttop surface 4115 c; the top surface of the light-emitting cavity formsMUX fixing glue grooves having an annular, protuberant circumference onwhich the wavelength division multiplexing component is disposed. Glueis provided into the groove enclosed by the annular, protuberantcircumference for adhering the wavelength division multiplexingcomponent. The first wavelength division multiplexing component 4601 isfixed on the first top surface 4115 c by means of the first MUX fixingglue groove 4117, and the second wavelength division multiplexingcomponent 4602 is fixed on the first top surface 4115 c by means of thesecond MUX fixing glue groove 4118. In some embodiments of the presentdisclosure, the first MUX fixing glue groove 4117 is used for dispensingglue. When the first wavelength division multiplexing component 4601needs to be fixed, glue is dispensed into the first MUX fixing gluegroove 4117, and then the first wavelength division multiplexingcomponent 4601 is placed and arranged into the first MUX fixing gluegroove 4117, and a fixing of the first wavelength division multiplexingcomponent 4601 on the first top surface 4115 c is achieved when the gluesolidifies. Similarly, the second MUX fixing glue groove 4118 is usedfor dispensing glue. When the second wavelength division multiplexingcomponent 4602 needs to be fixed, glue is dispensed into the second MUXfixing glue groove 4118, and then the second wavelength divisionmultiplexing component 4602 is placed and arranged into the second MUXfixing glue groove 4118, and a fixing of the second wavelength divisionmultiplexing component 4602 on the first top surface 4115 c is achievedwhen the glue solidifies.

The second top surface 4116 is provided for carrying the firstlight-emitting assembly 470 and the second light-emitting assembly 480.In order to ensure that a height of the emission channel of the firstlaser assembly 470 is the same/consistent with a height of the inputchannel of a wavelength division multiplexing component 4601, and aheight of the emission channel of the second laser assembly 480 is thesame/consistent with a height of the input channel of the secondwavelength division multiplexing component 4602, a semiconductorrefrigerator 490 is provided on the second top surface 4116, a topsurface (upper surface) of the semiconductor refrigerator 490 is affixedonto the second top surface 4116, and a bottom surface (lower surface)thereof is configured to support and secure the first light-emittingassembly 470 as well as the second light-emitting assembly 480, so thatheat generated by the first light-emitting assembly 470 and the secondlight-emitting assembly 480 may be conducted/transferred to thesemiconductor refrigerator 490, thus realizing an effective heatdissipation of the light-emitting assembly.

The step between the first top surface 4115 c and the second top surface4116 realizes a height difference in the top surface of thelight-emitting cavity 4115. On one hand, by the step formed between thefirst top surface 4115 c and the second top surface 4116, a mountingsurface for the semiconductor refrigerator 490 may be lifted by thesecond top surface 4116, thereby lifting the first light-emittingassembly 470 and the second light-emitting assembly 480, so as tofacilitate an assembly of the first light-emitting assembly 470, thefirst wavelength division multiplexing component 4601, the secondlight-emitting assembly 480, and the second wavelength divisionmultiplexing component 4602; on the other hand, the step can also beused for limiting the position of the semiconductor refrigerator 490.

The notch 4114 is provided at a side of the housing assembly 410approximate to the circuit board 300, which is wrapped around an outsideof the second top surface 4116; a third notch 310 is provided in thecircuit board 300, at a side facing towards the housing assembly 410;when the circuit board 300 is inserted into the first notch 4114 of thehousing assembly 410, the two side walls of the third notch 310 wraparound/engage with the second top surface 4116, so that a distancebetween the light-emitting assembly and the circuit board 300 can beshortened. When the first laser assembly 4702 and the second laserassembly 4802 are electrically connected to the circuit board 300 bywire bonding, the length of the wiring between the first laser assembly4702, the second laser assembly 4802 and the circuit board 300 may bereduced.

FIG. 23 is a cross-sectional view of an assembly of a light-emittingassembly and a housing assembly 410 in an optical module according to anembodiment of the present disclosure. As shown in FIG. 23, the secondtop surface 4116 is located below the light-passing holes 4109 of thehousing assembly 410, one side face (top surface) of the semiconductorrefrigerator 490 is affixed to the second top surface 4116, the firstlight-emitting assembly 470 and the second light-emitting assembly 480are all affixed to the other side face (bottom surface) of thesemiconductor refrigerator 490. The first light-emitting assembly 470and the second light-emitting assembly 480 use a total of eight lasers.Heat generated by the lasers is conducted to the semiconductorrefrigerator 490. The heat from the semiconductor refrigerator 490 mayturn away from/bypass the light-passing holes 4109, and is conducted tothe upper surface of the housing assembly 410 from regions where nodrillings are formed in the housing assembly 410, and is then conductedto the casing of the optical module through thermally conductivematerial for heat dissipating.

In the embodiments of the present disclosure, the light-emittingassembly is disposed underneath the partition wall of the housingassembly, with the partition wall being provided above the top surfaceof the light-emitting cavity and jointed with the top surface of thelight-emitting cavity; the light-passing holes 4109 are provided in thepartition wall. A heat conduction for the light-emitting assembly may berealized via the partition wall, and the partition wall is the heatconduction path for the light-emitting assembly. The partition wallrealizes a separation of the light-receiving cavity and the slot in thelight-receiving portion and a connection thereof via the partition wall.In order to obtain a light path between the light-receiving cavity andthe slot, light-passing holes are provided in the partition wall. Thelight beam demultiplexed and output from the wavelength divisionmultiplexing component at the light-receiving end is transmitted to thelens assembly, and each beam output from the wavelength divisionmultiplexing component is conducted to a corresponding collimating lensthrough a light-passing hole 4109.

In order to facilitate a heat conduction of the light-emitting assembly,the upper and lower portions of the housing assembly 410 are integratedtogether, so that heat generated in the light-emitting end can beconducted via the housing assembly 410 (for example conducted to theupper surface of the housing assembly via the partition wall), and isthen conducted to the casing of the optical module through thermallyconductive material for heat dissipation, as shown by the arrow, whichimproves a heat dissipation efficiency of the light-emitting end.

At the side of the housing assembly 410 approximate to the optical fiberadapter are provided a third through hole 4119 and a fourth through hole4120 which are both communicated with the light-emitting cavity 4115.The third optical fiber adapter 603 is inserted into the light-emittingcavity 4115 through the third through hole 4119, for receiving aconvergent beam output from the first focusing lens 701; the fourthoptical fiber adapter 604 is inserted into the light-emitting cavity4115 through the fourth through hole 4120, for receiving the convergentbeam output from the two convergent lens 702.

In the embodiments of the present disclosure, the light-emitting cavity4115 comprises a top plate and side plates surrounding the top plate.The top plate and the side plates form a cavity structure for holdingthe first light-emitting assembly 470, the first wavelength divisionmultiplexing component 4601, the first converging lens 701, the secondlight-emitting assembly 480, the second wavelength division multiplexingcomponent 4602 and the second converging lens 702. At the bottom of theside plates of the light-emitting cavity 4115 is provided a third coverfixing glue groove 4115 a, such that the cover 403 may be in turnfixedly secured onto the light-emitting cavity 4115 by glue. In someembodiments of the present disclosure, the third cover fixing gluegroove 4115 forms a closed-loop structure at the bottom of the sideplate of the light-emitting cavity 4115, thereby an adhesive area forthe third cover 403 onto the bottom of the side plates of thelight-emitting cavity 4115 may be increased, so that the packagingreliability of the third cover 403 and the bottom of the side plates ofthe light-emitting cavity 4115 may be well guaranteed. In someembodiments of the present disclosure, at the bottom of the side platesof the light-emitting cavity 4115 is further provided a third repairingopening 4115 b which is provided at the edge on the bottom of the sideplate of the light-emitting cavity 4115 and is communicated with thethird cover fixing glue groove 4115 a. When the devices inside thelight-emitting cavity 4115 need to be repaired after the third cover 403and the light-emitting cavity 4115 were packaged, the third cover 403can be disassembled from the light-emitting cavity 4115 via the thirdrepairing opening 4115 b, and then the third cover 403 can be removedwithout damaging the third cover 403 or the light-emitting cavity 4115,thereby reducing the difficulty and cost of repairing.

The optical module according to the embodiment of the present disclosureutilizes an integrated metal housing assembly. The housing assembly isopened from the upper and lower surfaces for arranging thelight-emitting assembly and the light-receiving assembly respectively,and the light-emitting assembly and the light-receiving assembly areplaced/stacked one above the other; that is, the light-emitting assemblyand the light-receiving assembly share the separation board in themiddle of the housing assembly, with the light-receiving assembly beingdisposed on the upper side of the separation board, and thelight-emitting assembly being disposed on the lower side of theseparation board; one end of the circuit board is inserted into thehousing assembly; high-frequency wirings of the light-emitting assemblyand the light-receiving assembly are respectively routed on the upperand lower surface of the circuit board to avoid cross effects. Theintegrated structure of the light-emitting assembly and thelight-receiving assembly can solve the problem of insufficient overallspace of an optical module using discrete light-emitting assembly andthe light-receiving assembly, and is beneficial for a miniaturization ofthe optical module.

Finally, it should be noted that the foregoing embodiments are merelyintended to describe the technical solutions of the present disclosure,and shall not be construed as limitation. Although the presentdisclosure is described in detail with reference to the foregoingembodiments, one of ordinary skills in the art may understand thatmodifications still may be made to the technical solutions disclosed inthe foregoing embodiments, or equivalent replacements may be made tosome of the technical features. However, these modifications orequivalent replacements do not deviate the nature of correspondingtechnique solutions from the spirit and scope of the technique solutionsof the embodiments of the present disclosure.

What is claimed is:
 1. An optical module, comprising: a circuit board; ahousing assembly into which the circuit board is inserted, which isdivided by a separation board into a first portion and a second portionthat are stacked one above the other, wherein a light-emitting cavity isformed in the second portion, and a partition wall is provided in thefirst portion to separate the first portion into a light-receivingcavity and a slot that is arranged approximate to the circuit board,wherein the partition wall is provided with a plurality of light-passingholes via which the light-receiving cavity is in communication with theslot; an optical fiber adapter, which is arranged in the housingassembly at a side away from the circuit board, and is in communicationwith the light-receiving cavity; a light-emitting assembly, which isarranged in the light emitting cavity and is electrically connected tothe circuit board, wherein heat generated by the light-emitting assemblyis conducted to a surface of the housing assembly via the partitionwall; and a light-receiving assembly, which comprises awavelength-division multiplexing component, a lens array and alight-receiving chip, wherein the wavelength-division multiplexingcomponent is arranged in the light-receiving cavity for demultiplexing amultiplexed beam transmitted by the optical fiber adapter into multiplebeams of different wavelengths and transmitting the demultiplexedmultiple beams to the lens array through respective light-passing holes;wherein the lens array is arranged in the slot for converging themultiple beams transmitted through the light-passing holes onto thelight-receiving chip; wherein the light-receiving chip is arranged on anend surface of the circuit board that is inserted within the housingassembly for receiving the converged beams and converting them into acurrent signal.
 2. The optical module according to claim 1, wherein thelight-receiving cavity comprises a first light-receiving cavity, and theslot comprises a first slot, with the first light-receiving cavity beingin communication with the first slot via the light-passing holes; theoptical fiber adapter comprises a first optical fiber adapter that is incommunication with the first light-receiving cavity; the light-receivingassembly comprises a first light-receiving assembly, wherein the firstlight-receiving assembly comprises a first wavelength divisionmultiplexing component, a first lens array and a first light-receivingchip, wherein the first wavelength division multiplexing component isarranged in the first light-receiving cavity for demultiplexing amultiplexed beam transmitted by the first optical fiber adapter intomultiple beams of different wavelengths and transmitting the multiplebeams to the first lens array through corresponding light-passing holes;wherein the first lens array is arranged in the first slot forconverging the multiple beams transmitted through the light-passingholes onto the corresponding first light-receiving chip; wherein thefirst light-receiving chip is arranged on the end surface of the circuitboard that is inserted within the housing assembly.
 3. The opticalmodule according to claim 2, wherein a first collimating lens is furtherprovided in the first light-receiving cavity, and is arranged betweenthe first optical fiber adapter and the first wavelength divisionmultiplexing component for converting the multiplexed light beamtransmitted by the first optical fiber adapter into a collimated lightbeam and transmitting the collimated light beam to the first wavelengthdivision multiplexing component.
 4. The optical module according toclaim 3, wherein the first light-receiving assembly further comprises afirst reflecting prism, which is arranged in the first slot and caps thefirst light-receiving chip from above, for reflecting the light beamsoutput from the first lens array to the corresponding firstlight-receiving chip.
 5. The optical module according to claim 2,wherein the light-receiving cavity further comprises a secondlight-receiving cavity, and the slot further comprises a second slot;the second light-receiving cavity and the first light-receiving cavityare arranged side by side in a width direction of the housing assembly;the second slot and the first slot are arranged side by side in thewidth direction of the housing assembly; wherein the secondlight-receiving cavity is in communication with the second slot via thelight-passing holes; the optical fiber adapter further comprises asecond optical fiber adapter that is in communication with the secondlight-receiving cavity; the light-receiving assembly further comprises asecond light-receiving assembly, wherein the second light-receivingassembly comprises a second wavelength division multiplexing component,a second lens array and a second light-receiving chip, wherein thesecond wavelength division multiplexing component is arranged in thesecond light-receiving cavity for demultiplexing a multiplexed beamtransmitted by the second optical fiber adapter into multiple beams ofdifferent wavelengths and transmitting the multiple beams to the secondlens array through corresponding light-passing holes; wherein the secondlens array is arranged in the second slot for converging the multiplebeams transmitted through the light-passing holes onto the correspondingsecond light-receiving chip; wherein the second light-receiving chip isarranged on the end surface of the circuit board that is inserted withinthe housing assembly.
 6. The optical module according to claim 5,wherein a second collimating lens is further provided in the secondlight-receiving cavity, and is arranged between the second optical fiberadapter and the second wavelength division multiplexing components forconverting the multiplexed light beam transmitted by the second opticalfiber adapter into a collimated light beam and transmitting thecollimated light beam to the second wavelength division multiplexingcomponent.
 7. The optical module according to claim 6, wherein thesecond light-receiving assembly further comprises a second reflectionprism, which is arranged in the second slot and caps the secondlight-receiving chip from above, for reflecting the light beams outputfrom the second lens array to the corresponding second light-receivingchip.
 8. The optical module according to claim 1, further comprising acovering hood that caps the slot from above, wherein a lower side of thecovering hood is opened towards and is in contact with an upper surfaceof the circuit board.
 9. The optical module according to claim 1,wherein a first notch is provided at a side of the housing assemblyproximate to the circuit board, wherein the first notch is arrangedbelow the slot, and the circuit board is inserted into the housing viathe first notch.
 10. The optical module according to claim 9, wherein asecond notch is provided between the first notch and the slot, with analuminum nitride ceramic substrate being arranged in the second notch,wherein gaps between the aluminum nitride ceramic substrate and thehousing assembly and gaps between the aluminum nitride ceramic substrateand the circuit board are filled with insulating high thermalconductivity glue.
 11. An optical module, comprising: a circuit board; ahousing assembly, which is divided by a separation board into alight-receiving portion and a light-emitting cavity that are stacked oneabove the other, wherein the light-receiving portion is provided with aplurality of light-passing holes, wherein the circuit board is insertedinto the housing assembly; an optical fiber adapter, which is arrangedin the housing assembly at a side away from the circuit board, and is incommunication with the light-emitting cavity; a light-receivingassembly, which is arranged in the light-receiving portion and iselectrically connected with the circuit board; and a light-emittingassembly, which is arranged in the light-emitting cavity and iselectrically connected to the circuit board; wherein the light-emittingassembly comprises a wavelength division multiplexing component, a lensarray and a laser assembly, and the laser assembly, the lens array andthe wavelength division multiplexing component are disposed in sequencealong a light-emitting path, wherein the laser assembly is arrangedunderneath the light-passing holes for emitting multiple beams ofdifferent wavelengths; wherein the lens array is configured to convertthe multiple beams into multiple collimated beams; the wavelengthdivision multiplexing component is configured to multiplex multiplecollimated beams into a multiplexed beam and to couple the multiplexedbeam to the optical fiber adapter.
 12. The optical module according toclaim 11, wherein a first laser assembly, a third lens array, a firstwavelength division multiplexing component, a second laser assembly, afourth lens array and a second wavelength division multiplexingcomponent are provided in the light-emitting cavity; wherein the firstwavelength division multiplexing component and the second wavelengthdivision multiplexing component are arranged in parallel, the firstlaser assembly, the third lens array and the first wavelength divisionmultiplexing component are disposed in sequence along the light-emittingpath, and the second laser assembly, the fourth lens array and thesecond wavelength division multiplexing component are disposed insequence along the light-emitting path; a third optical fiber adapterand a fourth optical fiber adapter are provided at the side of thehousing assembly away from the circuit board, with the third opticalfiber adapter being disposed on an output optical path of the firstwavelength division multiplexing component, and the fourth optical fiberadapter being disposed on an output optical path of the secondwavelength division multiplexing component.
 13. The optical moduleaccording to claim 12, wherein a top plate of the light-emitting cavitycomprises a first top surface and a second top surface which is arrangedabove the first top surface and underneath the light-passing holes; thefirst laser assembly, the third lens array, the second laser assemblyand the fourth lens array are all fixed on the second top surface, andthe first wavelength division multiplexing component and the secondwavelength division multiplexing components are both fixed on the firsttop surface.
 14. The optical module according to claim 13, wherein asemiconductor refrigerator is provided on the second top surface, with atop surface of the semiconductor refrigerator being adhered to thesecond top surface; wherein the first laser assembly, the third lensarray, the second laser assembly and the fourth lens array are all fixedon a bottom surface of the semiconductor refrigerator, so that anemission channel of the first laser assembly is at the same level withan input channel of the first wavelength division multiplexingcomponent, and an emission channel of the second laser assembly is atthe same level with an input channel of the second wavelength divisionmultiplexing component.
 15. The optical module according to claim 13,wherein a first MUX fixing glue groove and a second MUX fixing gluegroove are provided on the first top surface, wherein the firstwavelength division multiplexing component is fixed on the first topsurface via the first MUX fixing glue groove, and the second wavelengthdivision multiplexing component is fixed on the first top surface viathe second MUX fixing glue groove.
 16. The optical module according toclaim 11, wherein the light-receiving portion comprises alight-receiving cavity and a slot that is approximate to the circuitboard, and a plurality of light-passing holes are provided between thelight-receiving cavity and the slot.
 17. An optical module, comprising:a circuit board, an upper surface of which is provided with alight-receiving chip, and a lower surface of which is provided with apad; a housing assembly, an upper surface of which is downwardlyrecessed to form a light-receiving cavity and a slot, with a partitionwall being provided between the light-receiving cavity and the slot,wherein the partition wall is provided with light-passing holes tocommunicate the light-receiving cavity with the slot; wherein a lowersurface of the housing assembly is upwardly recessed to form alight-emitting cavity; a first optical fiber adapter, which is arrangedat one end of the light-receiving cavity; a third optical fiber adapter,which is arranged at one end of the light-emitting cavity, with a notchbeing provided at the other end of the light-emitting cavity; alight-emitting assembly, which is arranged in the light-emitting cavityand is configured to transmit lights to the third optical fiber adapter;wherein one end of the circuit board protrudes into the light-emittingcavity via the notch; the pad is arranged in the light-emitting cavityand is connected with the light-emitting assembly by wires; an opticalcomponent, which is arranged in the light-receiving cavity and isconfigured to receive lights from the first optical fiber adapter; areflective mirror, which is disposed at the slot and reflects lightsfrom the optical component; and a light-receiving chip, which isarranged between the reflective mirror and the circuit board and islocated outside the housing assembly, and is configured to receivelights from the reflective mirror.
 18. The optical module according toclaim 17, wherein the light-emitting assembly is arranged on a topsurface of the light-emitting cavity above which the partition wall isprovided.
 19. The optical module according to claim 17, furthercomprising a covering hood; wherein the housing assembly furthercomprises a first cover and a third cover; wherein one end of thecovering hood is connected with the partition wall, the other endthereof is in cooperation with the circuit board, and the covering hoodcaps the slot and the light-receiving chip from above; wherein the firstcover covers the light-receiving cavity, and the third cover covers thelight-emitting cavity.
 20. The optical module according to claim 17,wherein a DeMUX fixing glue groove with an annular, protuberantcircumference is formed on a bottom surface of the light-receivingcavity, wherein the wavelength division multiplexing component isdisposed onto the annular, protruded circumference, wherein glue isprovided into a groove enclosed by the annular, protuberantcircumference for adhering the wavelength division multiplexingcomponent.